Since, in the case of an acrylonitrile-butadiene-styrene (ABS) copolymer resin, mechanical strength, such as impact resistance, and properties, such as moldability and gloss, are relatively satisfactory, it has been widely used in electric components, electronic components, office equipment, automobile components, and the like.
When an ABS copolymer resin is prepared by grafting an aromatic vinyl compound and a vinyl cyan compound monomer to a conjugated diene-based rubber latex in an emulsion polymerization method, the ABS copolymer resin generally exhibits advantages such as satisfactory property balance and superior gloss, compared to that prepared in a bulk polymerization method. Accordingly, an ABS copolymer resin is mainly prepared in an emulsion polymerization method.
In addition, when an ABS copolymer resin prepared by an emulsion polymerization method is mixed and processed with a styrene-acrylonitrile copolymer (SAN) and thus the properties of the SAN resin composition are maximally utilized, products can be varied and a high value can be created.
Meanwhile, impact strength of an ABS resin is affected by the structure or molecular weight of diene-based rubber latex particles, as seed particles, the molecular weight of an ABS shell, a structure between ABS particles and a SAN matrix, and the like. To improve impact strength of an ABS resin, a method of adjusting the concentration of an initiator, a reaction temperature, a molecular weight regulator, a monomer concentration, and the like was proposed.
However, since there is a limitation in improving impact strength of an ABS-based resin in the method of adjusting the concentrations of reactants or temperature, it is difficult to produce a product particularly requiring impact resistance by the method.